Effect of Density Fluctuations on Lower Hybrid Ray Tracing and q-Profile Evolution in Transport Simulations
To investigate Lower Hybrid (LH) wave propagation in tokamaks, it is important to model scattering of lower hybrid waves by density fluctuations inside the plasma in addition to standard ray-tracing because LH wave propagation can be strongly affected by scattering from density fluctuations. The scattering can have a significant effect on the q-profile evolution, which is important in predictive transport modelling, especially for ITB or hybrid plasmas. In this work, a simple technique to include the scattering in the FRTC code  is considered. The model can then be used in either interpretive or predictive transport simulations where LH heating is used. This work reports the first studies with the FRTC code coupled to the Weiland transport model  in order to take into account the scattering within JETTO transport code . The model is then used for interpretive studies of two LH pulses at JET. In interpretive modelling experimental profiles are used except for the q-profile which is predicted.